(1) Field of the Invention
The present invention relates to a thermally insulated cooking device comprising; an insulated container provided with an insulated outer lid, and a cooking pot provided with an inner lid, suspended in space inside the insulated container.
(2) Description of the Related Art
Heretofore as such a cooking device, there has been disclosed in FIG. 1 of Japanese Examined Patent Publication No. 4-28490, a thermally insulated cooking device comprising; an insulated container having an upper opening with first handgrips respectively provided on opposite sides thereof, a cooking pot having an inner lid, housed inside the insulated container so as to be freely inserted and removed, an insulated outer lid which is able to close off the upper opening, connecting portions located above the first handgrips and provided on the insulated outer lid or on the insulated container, for connecting between the inside and outside of the insulated container, and second hand grips fixed at their respective base ends to opposite sides of the cooking pot and protruding outwards through the connecting portions. With this thermally insulated cooking device, food such as stew is placed in the cooking pot, which is then closed With the inner lid, and heat applied to cook. After this, the cooking pot is suspended in space inside the insulated container, and the insulated outer lid closed, thereby keeping the cooking pot at a high temperature so that cooking can continue.
With the conventional technology thermally insulated cooking device, the cooking pot can be thermally insulated and thus kept at a high temperature so that cooking can continue. However with the insulated container, since the inside and outside are connected by the connecting portions, then there is the likelihood of a small drop in the interior temperature of the insulated container.
As a means to solve this problem, there is disclosed in FIG. 2 of Japanese Unexamined Patent Publication No. 3-188188, a heat retaining body which can be used repeatedly, having a heat retaining material which can be melted by microwaves provided inside a container formed from a heat resistant material which is transparent to microwaves. Consideration is given to placing this heat retaining body at the bottom of an insulated container, however with this arrangement there is a problem with poor safety of the heat retaining body.